"Whenever we placed Vivian on a new assignment, she mastered it with a quick study and was always ready to take on something new," the letter quoted Ziegler as saying. "Her enthusiasm was infectious, as was her curiosity about architecture and the world about her. The entire office at Ziegler Cooper Architects has Vivian and her family in our prayers."

Dean of Architecture Sarah Whiting remembered Guan as "very special in the way that she combined such enthusiasm and intelligence in her work and also for the energy that she brought to the school. We will greatly miss her."

In a statement Monday, Metro said preliminary information showed that a woman onboard a northbound train exited the train at the Main Street Square station with her bike. She reportedly proceeded to the intersection, got on her bike on Walker and started crossing the intersection when she was hit by a southbound train.

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Metro spokesman Jerome Gray said he did not know whether Guan was wearing earphones.

Guan was a member of Sid Richardson College and had been looking forward to returning home to New Zealand to be with her family before the fall semester, the letter said.